The baboon has long been used in biomedical research and for certain applications has considerable advantages over other primate species. Despite their widespread use in research, there is currently an acute shortage of baboons available for use. The UOHSC has the third largest baboon breeding colony in the U.S. and is committed to improving and expanding this national resource. A new corral breeding facility has just been completed to allow expansion of the existing colony to approximately twice the current size. As is well appreciated for macaques, viruses constituting the normal flora of research animals can have a considerable effect on research results and their validity. Baboons are known to harbor analogs of many of the herpesviruses and retroviruses known to infect humans and other primates. Despite many years of successful breeding of baboons by various institutions, no colonies of SPF baboons exist that are free of even one specific virus. The program proposed here will result in the beginning of a self-sustaining colony of baboons free of all known herpesviruses, four retroviruses, and SV40. To accomplish this goal, the investigators will establish serological and PCR tests for each of the 11 target viruses. These baboon viruses will include six herpesviruses [analogs of human herpes simplex virus (HSV), varicellazooter virus (VZV), cytomegalovirus (CMV), human herpesviruses 6 (HHV6), Epstein-Barr virus (EBV), and human herpesvirus 8 (HHV-8)), four retroviruses (simian foamy virus (SFV), simian retrovirus type D (SRV/D), simian immunodeficiency virus (SIV), and simian T cell lymphotropic virus (STLV)] and simian virus 40 (SV40). The investigators will recruit no fewer than 12 infant baboons into the SPF program in each of the first two years, and 14/year in years 3-5 of the program for a final total of at least 66 SPF baboons. Utilizing timed pregnancies, over a 1-2 week period, two infants will be removed from their dams within 12 hrs of delivery and hand-reared to six months of age. All infants will be repeatedly tested for each of the target viruses. At one year of age, larger social groups of four to six SPF animals will be formed. Beginning at two to three years of age, SPF animals will be integrated into larger socially compatible groups. These groups will eventually mature into small breeding harems of SPF animals. This approach will: 1) provide infants with an age-matched companion for socialization during their early period of development; 2) minimize opportunities for transmission of endogenous viruses to the infants from adult animals; and 3) allow the simultaneous elimination of many different viruses from SPF animals.